A stent-graft is typically used to provide a prosthetic intraluminal wall, e.g., in the case of a vascular stenosis or aneurysm, to provide an unobstructed conduit for blood in the area of the stenosis or aneurysm. A stent-graft may be endoluminally deployed in a body lumen, a blood vessel for example, at the site of a stenosis or aneurysm by so-called “minimally invasive techniques” in which the stent-graft is compressed radially inwards and is delivered by a catheter to the site where it is required, through the patient's skin, or by a “cut down” technique at a location where the blood vessel concerned is accessible. When the stent-graft is positioned at the correct location, the stent-graft is caused or allowed to re-expand to a predetermined diameter in the vessel.
Accurately positioning a stent-graft prior to deployment can present challenges, e.g., impaired blood flow. Furthermore, deployment of a stent-graft within a thoracic aorta (ascending aorta) brings about added maneuverability and placement challenges of higher blood flow rate and pressure as compared to lower flow and pressure conditions within an abdominal aorta (descending aorta). For these and other reasons, improvements in stent-grafts to facilitate deployment with less disruption of fluid flow during deployment would be of significant utility.